Double coil window balance



FIG. 1 is a front view of the double coil window balance.

FIG. 2 is a left-hand perspective view thereof;

FIG. 3 is a right-hand perspective view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The broken lines immediately adjacent the solid line disclosure of the shoe represent the bounds of the claim and all other broken lines are for illustrative purposes only. None of the broken lines form a part of the claimed design. 

The ornamental design for a double coil window balance, as shown and described. 